Milling equipment can be used for smoothing areas of existing pavement by removing bumps, upward projections, and other surface irregularities, removing paint stripes, and milling shallow recesses to receive roadway edging and marking tape. In general, roadway surface milling, planing, or reclaiming equipment can include a rotary driven cylindrical comminuting drum which acts to scarify and to mine the top portion of the asphaltic road surface in situ. Road planning machines are used to remove bumps and other irregularities on the surface of a road, runway, taxiway, or other stretch of pavement. This planing effect is typically achieved by grinding the paved surface so that the grinding depth may vary slightly, but the surface produced by the grinding unit is more level than the original surface. The road planning machine typically includes a grinding unit that is rotatably powered by a shaft coupled to an engine or motor. The grinding units can include individual cutter bits that are securely fixed to the grinding unit, but are removable for maintenance or replacement.